Defensive publication

ABSTRACT

A PROCESS FOR ISOMERIZING A MIXTURE OF CIS- AND TRANSDIMETHYL 1,4-CYCLOHEXANEDICARBOXYLATE CONTAINING A HIGH CONTENT OF THE CIS-ISOMER TO MIXTURES CONTAINING MUCH LARGER AMOUNTS OF THE TRANS-ISOMER BY HEATING THE ORIGINAL MIXTURE IN THE PRESENCE OF AN ACIDIC CATALYST WHICH IS INSOLUBLE IN THE MIXTURE OF CIS- AND TRANS-ISOMERS. THE INSOLUBLE CATALYST CAN BE REMOVED FROM THE REACTION MIXTURE BY FILTRATION OR DECANTATION, PERMITTING EITHER THE SUBSTANTIALLY PURE TRANS-ISOMER OR AT LEAST A MIXTURE OF CIS- AND TRANS-ISOMERS UNCONTAMINATED WITH THE CATALYST TO BE RECOVERED. THE RATIO OF CATALYST EMPLOYED WITH RESPECT TO THE CIS- AND TRANS-MIXTURE MAY RANGE FROM ABOUT 0.005 TO 1.0. WHEN OPERATING AT ATMOSPHERIC PRESSURE HEATING MAY BE AT A TEMPERATURE OF 200-265* C. CARRYING OUT THE REACTION OF SUPER-ATMOSPHERIC PRESSURES PERMITS THE USE OF HIGHER TEMPERATURES.

DEFENSWE PULICATION UNITED STATES PATENT OFFICE Published at the requestof the applicant or owner in accordance with the Notice of Dec.';16,1960, 869 O.G. 687. The abstracts of Defensive Publication applicationsare identified by distinctly numbered series and are arrangedchronologically. The heading of each abstract indicates the number ofpages of specification, including claims and sheets of drawingscontained in the application as originally filed. The files of theseapplications are available to the public for inspection and reproductionmay be purchased for 30 cents a sheet.

Defensive Publication applications have not been examined as to themerits of alleged invention. The Patent Ofiice makes no assertion as tothe novelty of the disclosed subject matter.

PUBLISHED NOVEMBER 30, 1971 PROCESS FOR THE ISOMERIZATION 0F DI- METHYLCES-1,4-CYCLOHEXANEDICARBOXYL- ATE TO THE TRANS-ISOMER John G. Thweatt,Rte. 11 37663, and Wayne V. Mc-

Connell, 1509 Ardmore Place 37664, both of Kingsport, Tenn.

Filed May 13, 1970, Ser. No. 36,997 lint. Cl. C07c 67/00, 69/74 US. Cl.260-468 R No Drawing. 6 Pages Specification A process for isomcrizing amixture of cisand transdimethyl 1,4-cyclohexanedicarboxylate containinga high content of the cis-isomer to mixtures containing much largeramounts of the trans-isomer by heating the original mixture in thepresence of an acidic catalyst which is insoluble in the mixture of cisand trans-isomers. The insoluble catalyst can be removed from thereaction mixture by filtration or decantation, permitting either thesubstantially pure trans-isomer or at least a mixture of cisandtrans-isomers uncontaminated with the catalyst to be recovered. Theratio of catalyst employed with respect to the cisand trans-mixture mayrange from about 0.005 to 1.0. When operating at atmospheric pressureheating may be at a temperature of 200-265" C. Carrying out the reactionat super-atmospheric pressures permits the use of higher temperatures.

